if (typeof Crypto == 'undefined' || !Crypto.util) {
  (function () {
    var base64map =
      'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';

    // Global Crypto object
    // with browser window or with node module
    // var Crypto = (typeof window === 'undefined') ? exports.Crypto = {} : window.Crypto = {};
    var Crypto = (exports.Crypto = {});

    // Crypto utilities
    var util = (Crypto.util = {
      // Bit-wise rotate left
      rotl: function (n, b) {
        return (n << b) | (n >>> (32 - b));
      },

      // Bit-wise rotate right
      rotr: function (n, b) {
        return (n << (32 - b)) | (n >>> b);
      },

      // Swap big-endian to little-endian and vice versa
      endian: function (n) {
        // If number given, swap endian
        if (n.constructor == Number) {
          return (
            (util.rotl(n, 8) & 0x00ff00ff) | (util.rotl(n, 24) & 0xff00ff00)
          );
        }

        // Else, assume array and swap all items
        for (var i = 0; i < n.length; i++) n[i] = util.endian(n[i]);
        return n;
      },

      // Generate an array of any length of random bytes
      randomBytes: function (n) {
        for (var bytes = []; n > 0; n--)
          bytes.push(Math.floor(Math.random() * 256));
        return bytes;
      },

      // Convert a byte array to big-endian 32-bit words
      bytesToWords: function (bytes) {
        for (var words = [], i = 0, b = 0; i < bytes.length; i++, b += 8)
          words[b >>> 5] |= (bytes[i] & 0xff) << (24 - (b % 32));
        return words;
      },

      // Convert big-endian 32-bit words to a byte array
      wordsToBytes: function (words) {
        for (var bytes = [], b = 0; b < words.length * 32; b += 8)
          bytes.push((words[b >>> 5] >>> (24 - (b % 32))) & 0xff);
        return bytes;
      },

      // Convert a byte array to a hex string
      bytesToHex: function (bytes) {
        for (var hex = [], i = 0; i < bytes.length; i++) {
          hex.push((bytes[i] >>> 4).toString(16));
          hex.push((bytes[i] & 0xf).toString(16));
        }
        return hex.join('');
      },

      // Convert a hex string to a byte array
      hexToBytes: function (hex) {
        for (var bytes = [], c = 0; c < hex.length; c += 2)
          bytes.push(parseInt(hex.substr(c, 2), 16));
        return bytes;
      },

      // Convert a byte array to a base-64 string
      bytesToBase64: function (bytes) {
        // Use browser-native function if it exists
        if (typeof btoa == 'function') return btoa(Binary.bytesToString(bytes));

        for (var base64 = [], i = 0; i < bytes.length; i += 3) {
          var triplet = (bytes[i] << 16) | (bytes[i + 1] << 8) | bytes[i + 2];
          for (var j = 0; j < 4; j++) {
            if (i * 8 + j * 6 <= bytes.length * 8)
              base64.push(base64map.charAt((triplet >>> (6 * (3 - j))) & 0x3f));
            else base64.push('=');
          }
        }

        return base64.join('');
      },

      // Convert a base-64 string to a byte array
      base64ToBytes: function (base64) {
        // Use browser-native function if it exists
        if (typeof atob == 'function')
          return Binary.stringToBytes(atob(base64));

        // Remove non-base-64 characters
        base64 = base64.replace(/[^A-Z0-9+\/]/gi, '');

        for (
          var bytes = [], i = 0, imod4 = 0;
          i < base64.length;
          imod4 = ++i % 4
        ) {
          if (imod4 == 0) continue;
          bytes.push(
            ((base64map.indexOf(base64.charAt(i - 1)) &
              (Math.pow(2, -2 * imod4 + 8) - 1)) <<
              (imod4 * 2)) |
            (base64map.indexOf(base64.charAt(i)) >>> (6 - imod4 * 2)),
          );
        }

        return bytes;
      },
    });

    // Crypto character encodings
    var charenc = (Crypto.charenc = {});

    // UTF-8 encoding
    var UTF8 = (charenc.UTF8 = {
      // Convert a string to a byte array
      stringToBytes: function (str) {
        return Binary.stringToBytes(unescape(encodeURIComponent(str)));
      },

      // Convert a byte array to a string
      bytesToString: function (bytes) {
        // 2017-7-1 更改为 return bytes， 注释为源码
        // return decodeURIComponent(escape(Binary.bytesToString(bytes)));
        return bytes;
      },
    });

    // Binary encoding
    var Binary = (charenc.Binary = {
      // Convert a string to a byte array
      stringToBytes: function (str) {
        for (var bytes = [], i = 0; i < str.length; i++)
          bytes.push(str.charCodeAt(i) & 0xff);
        return bytes;
      },

      // Convert a byte array to a string
      bytesToString: function (bytes) {
        for (var str = [], i = 0; i < bytes.length; i++)
          str.push(String.fromCharCode(bytes[i]));
        return str.join('');
      },
    });
  })();
}
